Gaya APA

Ping. (2013). Bantul: PT Alif Media.

Gaya Chicago

Ping. . Bantul: PT Alif Media, 2013. Text.

Gaya MLA

Ping. . Bantul: PT Alif Media, 2013. Text.

Gaya Turabian

Ping. Bantul: PT Alif Media, 2013. Print.